Endoscopic surgical techniques, including laparoscopic and arthroscopic techniques, are gaining wide acceptance and are being increasingly used. There are many benefits associated with these minimally invasive techniques, including reduced patient trauma, reduced risk of post-operative infection and a reduced recovery time.
Various types of surgical instruments have been developed for use with these endoscopic surgical techniques and procedures, including clip appliers for the occlusion and ligation of vessels or other conduits and tissues. Conventional clip appliers, as currently used in these endoscopic procedures, typically consist of a frame connected to an actuating mechanism. A pair of clip compressing devices or jaws are supported at the distal end of the frame. The jaws typically consist of a pair of opposing jaw members which are movable with respect to each other. Each of the jaw members may include a slot or other means for retaining each of the legs of a surgical ligating clip. The outer surfaces of the jaw members may include cam surfaces which allow for movement by the actuating mechanism. In this configuration, the jaws are actuated by sliding an outer frame member over the cam surfaces, thereby forcing the jaw members towards each other. The ligating clips are insertable between the jaw members and within the inner grooves.
A conventional ligating clip has a pair of outwardly extending legs connected at an apex. The legs typically extend in a V-shaped or U-shaped manner from the apex and then change directions angularly at a knee portion to extend outward from the apex.
There are several deficiencies associated with the conventional endoscopic ligating clip appliers as described and as currently used. For instance, when using a ligating clip applier in an endoscopic procedure, the instrument is initially inserted through a cannula of an endoscopic trocar so that the clip may be positioned on the vessel or other tissue. The size of the vessel or tissue to be ligated is limited by the size of the clip being applied. In general, a larger vessel or tissue requires a larger clip. However, the size of the ligating clip is limited, in part, by the internal diameter of the trocar through which the ligating clip applier must be inserted.
In one version of the conventional ligating clip applier as previously described, the clip is retained within the jaw members. The jaw members extend outwardly from the frame but the opening between the jaws remains in substantial alignment with the longitudinal axis of the clip applier. A clip is inserted into the open jaws or into the hollow frame which is then passed through a trocar and manipulated within the patient until it is positioned around the tissue to be clipped. In this configuration, the open jaw members supporting the outwardly extending legs of the clip, or alternatively, the hollow frame member holding the open clip must define a diameter smaller than the internal diameter of the cannula. Otherwise, the clip applier can not pass through the trocar cannula.
In an alternative clip applier configuration, where the jaws move in an orientation perpendicular to the longitudinal axis, the size of the clip is also limited by the inner diameter of the cannula. In this configuration, the length of the clip from the end of the legs to the apex (length) must be smaller than the inner diameter of the cannula. Therefore, the overall width and length of the clip are limiting factors with regard to insertion through a trocar.
Another deficiency associated with conventional ligating clip appliers is the difficulty the endoscopic surgeon encounters when attempting to control the position of the clip during application. Often times, a clip is either improperly applied or applied to the wrong location. In these instances, the surgeon is required to apply another clip to the appropriate location. In addition, the surgeon must now remove or leave in the patient, at least two clips. Thus, there is a need for an endoscopic clip applier and associated ligating clip which may be repositioned during surgery and is also easily removed from the applied tissue.
Yet another deficiency associated with conventional ligating clip appliers and ligating clips is that the legs of the clip typically protrude inwardly from the inner jaw surfaces of the clip applier. This makes manipulation of the clip applier and clip within the patient more difficult. In part, this is due to the configuration of the jaws of a conventional ligating clip applier, wherein the jaw members do not wholly retain the legs of the clip within their inner surfaces. In other clip applier configurations, the deficiency is due in part to the configuration of the clip which has legs protruding outwardly from the distal ends of the jaws.
What is needed in this field, is an endoscopic clip applier and associated clip which overcomes these deficiencies and which is easy to use by the endoscopic surgeon and is economical to manufacture.